lecture 2

Question 1

is a cylindrical structure that is slightly flattened anteriorly and posteriorly, and it runs
through the vertebral canal of the vertebral column
from the foramen magnum of the occipital bone
superiorly to the level of L1 or L2 inferiorly

Answer 1

spinal cord

Question 2

It is a major reflex center and conduction pathway between the body and the brain. Its inferior end tapers in to the

Answer 2

Conus Medullaris or
Medullary Cone (L1 or L2)

Question 3

is the tapers continuation of the conus
medullaris into the long filament of connective tissue,
covered with the pia mater

Answer 3

Filum Terminale

Question 4

is formed by the neuron cell bodies,

dendrites and neuroglia.

Answer 4

Gray matter

Question 5

the gray matter is shaped like the letter H or butterfly shape. The crossbar of the H, is formed by the

Answer 5

Gray commissure

Question 6

Gray commissure contains the narrow central cavity of the spinal cord, the

Answer 6

Central Canal.

Question 7

contains the cell bodies of the motor neuron

Answer 7

anterior column or horns

Question 8

consist the interneurons, which receive information from sensory neurons

Answer 8

posterior column or horns:

Question 9

Its axon also forms the ventral roots and forms the

Answer 9

preganglionic sympathetic fibers.

Question 10

is composed of myelinated and unmyelinated axons

These fibers allow the communication between different parts of the spinal cord and between the cord and brain

Answer 10

white matter of the spinal cord

Question 11

is situated between the anterior median fissure and the anterior lateral sulcus. Most of the fibers are motor fibers.

Answer 11

Anterior column or funiculus:

Question 12

is situated between the anterior lateral sulcus and the posterior lateral sulcus. It has ascending and descending fibers (sensory and motor)

Answer 12

Lateral column or funiculus

Question 13

is situated between the posterior lateral sulcus and the posterior median sulcus.

Answer 13

Posterior column or funiculus

Question 14

It has ascending fibers, fasciculus gracilis medial and fasciculus cuneatus lateral, separated by the

Answer 14

posterior intermediate sulcus

Question 15

start in higher centers (cortex)
send “commands” to Lower Motor Neurons
(LMNs)
lesion leads to spastic paralysis (hyperreflexia and
hypertonia)

Answer 15

Upper Motor Neuron

Question 16

start in the spinal cord (ventral horn cells) and
brainstem (cranial nerve nuclei)
directly “command” muscles to contract via
spinal and cranial nerves
Lesion leads to flaccid paralysis, hyporeflexia,
or areflexia

Answer 16

Lower Motor Neurons

Question 17

are formed by the union of the anterior (motor) root and the posterior (sensory) root; therefore the
spinal nerves are mixed

Answer 17

spinal nerves

Question 18

After emerging from the intervertebral foramen, each spinal nerve immediately divides into a large

Answer 18

anterior ramus and a small posterior ramus

Question 19

postganglionic fibers to glands and smooth muscles

Answer 19

gray communicating ramus

Question 20

a short branch with preganglionic visceral motor fibers from the lateral horn to the autonomic ganglia

Answer 20

white communicating ramus

Question 21

branch from the spinal nerve and re-enter the intervertebral foramen to serve the ligaments, dura,
blood vessels, intervertebral discs, facet joints, and periosteum of the vertebrae.

Answer 21

recurrent ramus or meningeal

Question 22

filled with fat and the internal vertebral venous plexus

Answer 22

Epidural space

Question 23

is the space between the arachnoid mater and pia mater, which is filled with cerebrospinal fluid.

Answer 23

Subarachnoid space:

Question 24

that attach the spinal cord to the dura mater,
and thus help to suspend the cord within the
subarachnoid space.

Answer 24

denticulate ligament

Question 25

is formed by union of two arteries arises from the vertebral artery

Answer 25

Anterior spinal artery

Question 26

are two in number, arises either from the posterior inferior cerebellar arteries or from the vertebral arteries

Answer 26

Posterior spinal arteries:

Question 27

These arteries are branches of arteries outside the vertebral column (deep cervical, posterior intercostal and lumbar arteries) that enter through the intervertebral foramen.

Answer 27

Segmental spinal arteries